Orthopedic equipment, such as prostheses and orthoses require moulding with which the the equipment can be joined to the body. Alongside standard mouldings in various sizes, mouldings which have been specially adapted to the relevant bodies of the patients are often used. The production of these specially adapted mouldings occurs conventionally by means of an impression of the relevant body using a suitable material, such as plaster. This mould is made by an orthopedic technician who regularly sends the mould to a production company for orthopedic equipment, in order to have a piece of orthopedic equipment made to a specially adapted moulding, particularly an orthosis. For the moulding of an orthosis it is required, for example, to produce a positive mould with the plaster impression, which corresponds to the shape of the body part. With this mould, the design of the real orthopedic moulding is made. This process is not only time-consuming, but also requires the production of moulds which are only used once, which increases the price of the orthopedic equipment.
In WO 2008/092443 it is described that an orthopedic moulding in its finished form is arranged directly onto the body of the patient by providing the layers joined to each other with a plastic deformable insert which holds the deformation caused by the adaptation (draping) on the relative body part until the layers are joined by the hardening of a binding material. The production of the moulding must occur immediately after the impression, i.e. regularly at the orthopedic technician. This causes considerable restrictions on the production of the orthopedic equipment, which in many cases occurs in a specialized production company that has specialized production devices and testing facilities.
In US 2002/0177797 A1 orthopedic arrangements are described which comprise the support elements, which can be hardened, that can be adapted to a body part of the patient. These flat elements are impregnated in the middle part with a material that can be hardened, whilst the edge is free of this material. Following the adaptation to the body of the patient the element is hardened in the conventional way.
In US 2008/0319362 A1 a system is described for immobilizing and supporting of a body part where an in situ hardening should be explicitly avoided.
The U.S. Pat. No. 6,129,695 discloses joint protectors, such as those worn by athletes, for example. These sorts of protectors are provided with cushions or foam pads, for example, in order to produce a better protective effect. Should the various components of this sort of joint protector be sewn together, the wearer can experience irritation caused by the seams. In order to prevent this, it is suggested to join the various parts to each other using a thermoplastic material which is melted to join the parts. This occurs during the production of the protector by means of a heat electrode which is pressed onto the materials to be joined.
In GB 2 349 822 a splint is described with which the body parts can be splinted and immobilized. This comprises a case that is filled with a thermoplastic material. To adapt the splint to the body part, the material is heated and becomes fluid. Once it has cooled down, the splint remains in the shape adapted to the body part.
The above invention therefore aims to enable the production of a moulding, the necessary dimensional stability of the moulding being achieved easily and with little effort during or immediately after the moulding process of the initial mould.
To solve this aim, a process according to the invention like that mentioned at the beginning is characterized by the fact that, in the arrangement made of layers, at least one converter element is introduced that transforms supplied energy into heat energy and with which at least parts of the layers are heated to join the layers.
Accordingly, to solve the identified aim an orthopedic moulding arrangement according to the invention like that mentioned at the beginning is characterized by the fact that in the arrangement made of layers at least one converter element is introduced that transforms supplied energy into heat energy and with which at least parts of the layers are connected.
According to the invention it is thus intended that the layers joined to each other under the influence of heat are deformed (draped) by adapting them to the initial mould, especially to the body shape, and that the layers are joined to each other following deformation by supplying energy to the converter element. This energy supply creates the heat required to join the layers to each other.
A simple converter element is a heating conductor which has been introduced in the layer arrangement that can preferably be arranged between at least two layers. The connectors of this heating conductor are then led out of the layer arrangement. By means of a current through the heating conductor, the heat required to join the layers to each other can be generated.
In another embodiment, an arrangement that absorbs microwaves can be inserted into the layer arrangement, which can be heated very quickly by a short exposure to microwaves and thus generates the heat required to join the layers to each other. Moreover, the converter elements can be formed by electric conductors that are heated by electro-magnetic fields created by induction coils. In this case, it is not necessary to lead the connectors out of the layer arrangement. Of course, other converter elements and ways to energize the converter elements are deployable, to which the energy can be supplied in a selective way. Alongside high frequency energy, the supply of, for example, ultrasonic energy comes into question for the generation of the necessary heat. It is essential for the invention that the heat is generated in the area around the converter elements and not in the layer material itself. These should at most be only marginally heated by the energy supply, and obtain the energy required for joining from the heated converter elements.
In a preferred implementation of the above invention, the joining of the layers is only temporarily produced, especially in order to be able to transport the mould taken from the body part safely to the production company for the orthopedic equipment. The joining of the layers is so stable that the mould taken remains intact during transportation to the production company. However, in this case it is not stable enough to withstand the loads during use of the orthopedic equipment, such as orthoses. Accordingly, a permanent joining of the layers does not take place in this case until it reaches the production company for orthopedic equipment. As a result, it is sufficient for this type of implementation that the joining of the layers only occurs locally, for example only in close proximity of a heating wire or a heating strip. For this purpose, joining the layers across the entire surface is neither required nor practical.
The joining that is carried out between the layers by the supply of heat can occur by means of a thermosetting material or a thermoplastic material. With a thermosetting material, the hardening occurs by means of a chemical transformation at higher temperatures. Here, the joining is usually permanently fixed. The joining with a thermoplastic material is preferable. The layers themselves can then be made from a thermoplastic material or be coated with a thermoplastic material, the layers still being separated from each other. The supply of heat then leads to a softening of the thermoplastic material, which causes the layers within the vicinity of the fluid thermoplastic material to join together when the thermoplastic material solidifies after cooling down. The same effect can be achieved by placing a thermoplastic intermediate layer in between the layers, for example in the form of a thermoplastic foil.
In a preferred embodiment, the layers are fiber layers, preferably fabric layers. This means that fiber layers impregnated with thermoplastic material, so-called prepregs, can be implemented. Furthermore it is possible to use fiber layers with fibers that have a fiber core which is coated with a thermoplastic casing. With a suitable control of the influence of heat, uncoated thermoplastic fibers can also be used. In this case it is advantageous if only the surface of the fibers is melted under the influence of heat.
For the retention of the deformation of the layers generated by pressing them against the body part, the layers can be arranged in a gas-proof casing in a manner known, which can be evacuated before and especially after deformation. The formation of a vacuum creates a manageable layer pack that is dimensionally stable against low loads. This evacuated layer pack can thus be removed from the body part and then the joining between the layers according to the invention can be produced. In this way, by using only locally arranged converter elements, such as with a few turns of a heating wire, it is possible to produce such a stable joining between the layers that the moulding produced can be transported so that it remains dimensionally stable, even if the layer is not (or no longer) situated in a vacuum.
However, a permanent joining of the layers according to the invention also is not to be ruled out if a correspondingly extensive application of heat on the layers is guaranteed, resulting in an extensive joining between the layers.